In Trauma and Orthopaedics, weight bearing refers to how much weight or force is put through a specific limb. As per the British Orthopaedic Association Standards for Trauma (BOAST) guidelines, all patients should have a clearly documented rehabilitation plan, including weight-bearing status, after a musculoskeletal injury or orthopaedic surgery, as it forms an integral part of their mobilisation plan.¹ This guideline was developed to help standardise the different weight-bearing terms used in practice.
Contents
Non-Weight Bearing (NWB)
NWB means the patient should not put any weight through the affected limb(s). An example of this would be a patient who has had a fracture treated non-operatively through manipulation and application of a plaster cast (usually a half cast or backslab in acute injuries to allow for expected soft tissue swelling). This may be the definitive treatment until the fracture heals or a temporary measure prior to definitive surgical fixation.
Limited Weight Bearing
Limited Weight Bearing refers to when a patient can put a proportion of their weight through the affected limb(s), ideally given as a percentage. Commonly this is with the support of crutches or a frame. An example would be after fixation of an undisplaced intracapsular neck of femur fracture with cannulated screws.
Unrestricted Weight Bearing
Unrestricted Weight Bearing is more commonly referred to as full weight bearing (FWB), meaning the patient can put 100% of their weight through their affected limb(s). An example of this would be a stable ankle fracture treated conservatively with a walker boot. The aim is to encourage early mobilisation to reduce complications such as DVT and deconditioning.
Other Commonly Used Terms
Weight bear as tolerated (WBAT) is used to describe when a patient may place as much weight on the affected limb as pain and comfort allow; there is no mechanical restriction, but pain is the limiting factor.
Terms such as protected weight bearing, toe touch weight bearing, and partial weight bearing all fall under the limited weight-bearing category. BOAST advises clinicians to use these terms with caution, as they can sometimes be interpreted differently in practice and may not always provide a clear understanding of how much weight is permitted.
References
- BOAST Guideline on Mobilisation and weightbearing after orthopaedic surgery / musculoskeletal injury https://www.boa.ac.uk/resource/mobilisation-and-weightbearing-after-orthopaedic-surgery-musculoskeletal-injury-boast.html
Written by Dr A Sidhu (CT2)
